A hybrid vehicle using a high voltage battery includes a system that automatically shuts off power of a main high voltage battery in an emergency. The emergency refers to excessive electric leakage due to deterioration of related components or excessive electric leakage due to a short-circuit caused by component breakdown as a result of external shock, such as dielectric breakdown, dielectric breakdown, and so on.
In a state of emergency of a vehicle, an upper component for controlling a high voltage component such as a battery management system (BMS), a hybrid controller (HC), or the like issues a command for shutting a main power to power off.
A high voltage related component monitors a voltage and current of a connecting path for the power via a predetermined program or sensor. In this case, when the detected voltage or the current is outside a normal range, or a leakage current value is greater than an allowable value, and a dielectric resistance breakdown value which is greater than the allowable value are present, the main power is shut off via CAN communication or signal transmission.
With respect to the hybrid vehicle, a fuel battery vehicle and the like that use the high voltage battery, it is important to measure dielectric resistance. The dielectric resistance is measured by using various methods. During the measurement of the dielectric resistance, resistance between chassis ground and the high voltage battery is measured to determine whether or not dielectric breakdown occurs.
In this case, when the detected and measured dielectric resistance value is greater than the allowable value, or a component such as a low voltage direct current (DC) converter (LDC), an on-board charger (OBC), a positive temperature coefficient (PTC), an air conditioner (A/C), an inverter, a motor, and so on as well as a high voltage component such a battery management system (BMS), a hybrid controller (HC), a fuel cell controller (FC), and so on is abnormal, the dielectric resistance value which is greater than the allowable value may be detected.
However, conventionally, when the dielectric breakdown such as a stop state, a drive state, a regenerative braking state, and so on of the vehicle occurs, whether or not the dielectric breakdown occurs is simply examined, and it is not possible to check an actual faulty component. Accordingly, a relay of the high voltage battery is powered off to handle the dielectric breakdown. In this case, even though driving is possible without the faulty component, when the detected dielectric resistance value is equal to or greater than the allowable value, since the relay of the high voltage battery is powered off, driving is not possible.
The description of the related art is to aid in understanding of the present disclosure and is not to be construed as conventional arts that are already known to those of ordinary skill in the art.